The present invention relates to a semiconductor device, such as a CMOS-FET (Complementary Metal Oxide Semiconductor Field Effect Transistor) and the manufacturing method thereof.
In recent years, with needs of further miniaturization and higher functionality of electronic devices, for example, enhancement of carrier mobility has been studied to increase a driving force in a CMOS-FET for configuring a SRAM (Static Random Access Memory) cell.
It has been known that the carrier mobility depends upon a wafer plane orientation or an axial direction to be used or stress such as lattice strain, and the direction of the enhancement or degradation thereof is different between an n-type MOS-FET with an electron as a carrier and a p-type MOS-FET with a hole as a carrier. For example, if a <110> axial direction of a Si wafer (100) face is taken as a channel longitudinal direction, tensile stress is applied for an N-type MOS-FET and compressive stress is applied for a P-type MOS-FET, in the channel longitudinal direction (X-direction) and a direction (Z-direction) perpendicular to a wafer face, respectively. In a channel width direction (Y-direction), tensile stress is applied to each thereof. Application of such stress can enhance carrier mobility.
As an approach to each stress application, there have been proposed an approach to applying tensile stress by forming an SiN film having tensile stress at an isolation part of STI (Shallow Trench Isolation), an approach to applying compressive stress by epitaxially growing a SiGe layer having a higher lattice constant than Si and an approach to forming an insulation film having tensile stress or compressive stress on an electrode.
There has been also used an approach to applying stress suitable to respective elements by individually preparing the respective elements one by one, as disclosed in Japanese Patent Application Laid-Open No. 11-340337 and Japanese Patent Application Laid-Open No. 2006-165335. However, necessity of the individual preparation process causes inconveniences such as an increasing of the number of processes and affects on peripheral processes.